David Collins, a member of the First Fleet and Australia’s first Deputy Judge Advocate, recalled that selecting criminals to oversee the colony’s law and order was not an easy choice.

“It was to be wished, that a watch established for the preservation of public and private property had been formed of free people, and that necessity had not compelled us in selecting the first members of our little police, to be appointed from a body of men in whose eyes, it could not be denied, the property of individuals had never been sacred,” Collins wrote.

But with little other manpower available, there was no other choice. The 12 men who were organised into four groups to patrol different areas of the settlement.

In 1790, another delegation of convicts was selected to become part of the Sydney Foot Police, extending the police jurisdiction as far as Toongabbie, Hawkesbury and Parramatta.

The force was re-organised along similar lines to the London Police by Governor Hunter in 1796, with constables falling under the purview of local magistrates.

Within 30 years, Sydney had more than 60 constables, most of whom were former convicts.

In the next few decades, other groups of police were added including the Mounted Police (originally a military unit), Water Police, Border Police and the Mounted Aboriginal Police Unit.

The responsibilities of the Mounted Police included protecting settlers in far-flung places and security for the transport of goods, including gold.

The most important of these specialised forces was the Mounted Police, which had the responsibility of protecting settlers in outlying areas as well as goods in transit on the roads

In the 1850s, the Police Recruiting Act enable recruitment from the British Isles. New officers received free passage to Australia in exchange for three years of police service.

So how did the police force made up entirely of criminals fare? Apparently quite well.

While there are no official crime statistics available, letters and notes written at the time mention a strong decline in the high crime rates that plagued the colony.